With the advancement of a variety of portable apparatuses in recent years, many batteries are used widely in light of convenience in portability and general versatility, such as AA-type alkaline storage batteries (type LR6), and the like.
On the other hand, small secondary batteries like rechargeable nickel metal hydride storage batteries, and lithium ion secondary batteries are expanding their market rapidly, including applications in the fields of cellular phones, laptop computers, video cameras, and the like.
Alkaline dry batteries are readily available and easily usable. However, they are high in running cost, and heavy in environmental load, because they are disposed of when completely discharged in headphone stereos and digital cameras, for instance.
On the other hand, although the secondary batteries are superior in cost performance including their running cost, they are not quite popular because of such reasons as high initial cost, time to recharge which requires fully-charged spare batteries ready to use in case of replacement, high price of battery charger, and so forth.
In addition, even though the secondary batteries consume a smaller amount of natural resources than the primary batteries because they can be recharged many times for repeated use, a ratio of their reclamation is only about 10% at the most since collection of those once-sold secondary batteries is dependent only upon goodwill of the individual users.
Because of the above reasons, there were proposed a number of ideas, such as recharging collected secondary batteries and reselling them as second-hand goods, renting secondary batteries to the users with collateral recharge service, and the like.
Japanese Patent Unexamined Publications, (1) H03-41594, (2) 2001-283931, (3) S61-501289, (4) H01-173289, (5) H10-293874, (6) H11-150809, (7) 2000-90348, and (8) 2001-23037 are some examples of the ideas (these publications are referred to as prior art examples 1 through 8).
The prior art example 1 discloses a vending machine used to sell second-hand secondary batteries that are collected and classified according to their levels of quality. However, the vending machine provided on a site where secondary batteries are exchanged with users (may also be referred to as “location”) needs to be a large scale piece of equipment, if the batteries are classified properly according to their levels in addition to the reuse process such as recharging. Furthermore, the recycle rate would likely lower a significant amount, if the vending machine executes at the site only a simple process of inspection and revitalization for reuse.
In addition, secondary batteries applicable to this vending machine are limited to small sealed lead-acid batteries as described in this prior art example 1, since they are the only batteries, capacities of which can be determined based on open-circuit voltages and internal impedance. Thus, the invention is not applicable to nickel metal hydride batteries and lithium rechargeable batteries which have been mainly used in recent years.
Moreover, although the prior art example 1 makes reference to recovery of resources by recycling, an anticipated rate of recovery would be considerably low in reality, since collection of used batteries depends solely upon goodwill of the users once they were sold to them, as described above.
On the other hand, prior art example 2 discloses a method of providing exchange services, in which discharged secondary batteries used by users are replaced with fully-charged secondary batteries.
However, the disclosed method takes some time to complete, and it does not provide prompt service, because it requires time to execute placement of a tag for controlling the history of each secondary battery in addition to recharging it at a site where batteries are brought in and exchanged with those of users.
In addition, since degradation of the secondary batteries varies according to conditions of use by individual users, it is not possible to assure quality of the batteries when being used by the users, if they are controlled simply by time and number of usages. It also makes the recycling difficult when all secondary batteries that have exceeded certain usable periods are discarded automatically, since this leads to disposal of the unusable batteries without separating them into groups each with the same kind of batteries.
In other words, none of the above examples provides a sound method of assuring quality of the secondary batteries easily on the site where the secondary batteries are exchanged with those of users.